1. Field of the Invention
The present invention relates to a disc cartridge which rotatably accommodates a disc-shaped disc medium used as a recording/playback medium of an information processing device or the like, and which prevents entry of dust or the like.
2. Description of the Related Art
A disc-shaped disc medium, such as an optical disc, a magneto-optical disc, or the like, is used, for example, as a portable recording/playback medium for a computer. When recording or playback of the disc medium is carried out, laser beam is illuminated onto the recording surface while the disc medium is rotated in a state of being loaded in a drive device. In this way, recording of information is carried out by pit formation or phase changes or magnetization or the like due to decomposition of the dye layers of the recording surface, or recorded information is played back on the basis of differences in the reflectivity or the polarizing angle of the laser beam.
Accordingly, there are disc media in which, when information is recorded on such a disc medium, it can be visually confirmed to what point recording has been carried out. Namely, the regions at which information is recorded/unrecorded can be judged due to the hue of the recording surface of the disc medium changing.
Further, in such disc media, shortening of the wavelength of the laser beam which is illuminated onto the recording surface has been proposed in order to increase the recording capacity. When recording or playback of information is carried out by using this short-wavelength laser beam (e.g., a blue-violet color laser), in order to suppress the attenuation of the laser beam due to the cover layer which protects the recording surface of the disc medium, the cover layer must be made thin. By making the cover layer thin in this way, the diameter of the laser beam at the surface of the cover layer (the surface which is exposed to the exterior) decreases, and it is not possible to ignore the effects of dust and the like adhering to the surface of the cover layer.
Thus, disc cartridges, which accommodate a disc medium in a case and prevent adhesion of dust or the like onto the disc medium, are employed. Such a disc cartridge is formed to include an opening, which is for exposing to the exterior a center hole portion (center core portion) provided at the central portion of the disc medium and a portion of the recording surface (the cover layer), and a shutter member which opens and closes this opening.
In this way, in the disc cartridge, by closing the opening by the shutter member when the disc medium is not in use, entry of dust or the like into the disc cartridge, i.e., adhesion of dust or the like onto the disc medium, is prevented. At the time when the disc medium is used, by opening the opening as the disc cartridge is loaded into the drive device, the center hole portion (the center core portion) can be held by a rotation spindle shaft, and the laser head can approach the recording surface (laser beam can be illuminated).
However, in such a disc cartridge, even if the disc medium is such that information recorded/unrecorded regions can be visually judged by a change in the hue of the recording layer, because the disc medium is housed in a case, if the disc cartridge is not loaded into a drive device, it is not possible to recognize the correct unrecorded amount. Thus, it is inconvenient for the user of the disc cartridge, and the ability to easily visually recognize the approximate unrecorded amount of the disc medium has been desired in the conventional art.
Further, in such a disc cartridge, in the aforementioned state in which the opening is open, there is the need to ensure a space for accommodating the shutter member, and a problem arises in that it is difficult to make the disc cartridge compact. Thus, to aim for compactness, a disc cartridge in which the shutter member is divided in two has been disclosed in Japanese Patent Application Laid-Open (JP-A) No. 2000-30394 and the like. In the disc cartridge of JP-A 2000-30394, the entire opening is closed in a state in which the end surfaces of a first shutter member, which mainly closes the opening portion for laser head insertion (approach), and a second shutter member, which mainly closes the opening portion for insertion of the rotation spindle shaft, abut one another.
When this disc cartridge (disc medium) is to be used, it is loaded (inserted) into a drive device. Along with this loading, a lock releasing lever, which is disposed within an arm guide groove, is operated, and a moving operation portion, which is connected to the first shutter member, is moved along the arm guide groove. In this way, the first shutter member is rotated in the direction of opening the opening while a circular-arc-shaped guide portion of the first shutter member slides along a tubular inner wall provided at a case.
Further, along with this rotation, the second shutter member is pressed by a convex portion of the first shutter member which abuts an engagement portion of the second shutter member. The second shutter member rotates in a direction of opening the opening, which is different than that of the first shutter member. In this way, the first shutter member and the second shutter member are accommodated within accommodating spaces which substantially correspond to the projection surface area of the disc-shaped disc medium. Thus, this disc cartridge aims for a reduction in size and a reduction in thickness, while preventing adhesion of dust and the like onto the disc medium.
With such a conventional disc cartridge, at the time of closing the opening which has been opened, due to the urging force of a torsion spring which urges the second shutter member in the closing direction, not only is the second shutter member rotated, but also, the first shutter member, whose sliding resistance accompanying rotation (mainly, the sliding resistance between the guide portion and the inner wall) is large, is also rotated. Thus, there are cases in which the operations of the first shutter member and the second shutter member are not carried out smoothly. Further, in order to make these operations smooth, excessive machining precision and assembly precision are required at each portion, which is a cause of high costs.
Moreover, in order to rotate the first shutter member as well, the spring constant of the torsion spring must be made large, and a problem arises in that the handling of the torsion spring is complex and the assemblability thereof is poor. In particular, because the torsion spring is disposed in a vicinity of the rotation shaft of the second shutter member, the spring constant must be made even greater. This problem becomes marked, and the torsion spring itself must be made larger. A problem arises in that either the entire disc cartridge becomes larger sized, or the regions of operation of the respective shutter members become smaller (i.e., the opening becomes smaller and cannot handle large-sized laser heads or the like).
On the other hand, JP-A 2000-30394 also discloses a structure in which the moving operation portion, which is connected to the first shutter member, is moved in the direction opposite to the time of opening the opening, and the first shutter member is rotated in the closing direction. However, the connecting portion, which connects the first shutter member and the moving operation portion, is structured as an elastic thin plate in order to convert the rectilinear direction moving force of the moving operation portion into circumferential direction moving force which rotates the first shutter member. Thus, no problems arise in the operation in the pulling direction (the direction of opening the opening), but it is easy for deformation such as buckling or the like to occur due to operation in the compressing direction. Therefore, in this disc cartridge, there are cases in which, when a disc medium is used, the opening which has been opened cannot be closed.
Further, as shown in FIG. 27, in the case of a disc cartridge 170 which rotatably accommodates a disc-shaped disc medium 180 within a case which is formed by a top shell 174 and a bottom shell 172 being joined together, at the bottom shell 172, an opening 178, by which the disc medium 180 can be accessed, is formed by being cut-out from an end portion in a substantial U shape as seen in plan view. Shutter members 182, 184, which open and close the opening 178, are movably accommodated between the bottom shell 172 and a covering plate portion 176 in which a similar opening 190 is formed.
Accordingly, it is desirable that the bottom shell 172 be manufactured by injection molding or the like by a resin member or the like which increases the slidability, i.e., the rotatability, of the shutter members 182, 184. However, the opening 178 formed in the bottom shell 172 is formed by being cut-out in a substantial U shape as seen in plan view. Thus, twisting due to strain or the like at the time of injection molding, e.g., forces in opposite directions as shown by arrows E, F in the figure, may be applied to distal ends 186, 188, which oppose one another across the cut-out substantial U shape, and flexural deformation, such as the bottom shell 172 twisting, may arise.
When such twisting (flexing) arises at the bottom shell 172, the rotatability of the shutter members 182, 184 deteriorates, and the drawback arises that the openings 178, 190 of the disc cartridge 170 do not open smoothly. Further, the shutter members 182, 184 inappropriately contact the bottom shell 172, and dust or the like is generated. Due to this dust or the like adhering to the recording surface of the disc medium 180, the drawback may arise that it will lead to errors at the time of recording and playback.
Moreover, when such a disc cartridge is loaded into a drive device, it suffices for the force for pushing-in the disc cartridge to be applied parallel to the loading direction. However, for example, if a vicinity of a corner portion of the disc cartridge is pushed and force is applied in a diagonal direction, because the disc cartridge is flat and there is little difference in the front-back and left-right lengths thereof, the disc cartridge lacks a regulating force which regulates, in the loading direction, the force applied in the diagonal direction, and a drawback arises in that it is difficult to load the disc cartridge into the drive device.
The object of the present invention is to provide a disc cartridge which accommodates a disc medium which can be recorded at least one time and in which the recorded/unrecorded regions can be visually identified, wherein the unrecorded amount can be easily recognized visually from the exterior, a pair of shutter members are smoothly operated such that an opening for accessing the disc medium accommodated in the interior can be reliably closed, the flatness of a case can be ensured such that the rotatability of the shutter members does not deteriorate, and loading into a drive device can be carried out smoothly and stably.
In order to achieve the above object, the disc cartridge of a first aspect of the present invention is a disc cartridge provided with a case which accommodates a disc-shaped disc medium at which information recorded/unrecorded regions can be visually identified, wherein a visual recognition portion for enabling visual recognition of the recorded/unrecorded regions is provided at a disc medium recording surface side of the case.
With such a structure, the recorded/unrecorded regions of the disc medium can be easily visually confirmed from the exterior. Thus, the approximate unrecorded amount of the disc medium can be easily recognized, and the convenience of use of the disc cartridge can be improved as compared to the prior art.
The disc cartridge of a second aspect of the present invention is a disc cartridge having: a case which is formed by joining a top shell and a bottom shell, and which rotatably accommodates a disc-shaped disc medium which can be recorded on at least one time and at which recorded/unrecorded regions can be visually identified; an opening, provided in the case, for access to the disc medium; a shutter portion which is provided at an outer side of the case and at a disc medium recording surface side of the case, and which opens and closes the opening; and a covering plate portion in which an opening for access to the disc medium is formed, the shutter member being movably accommodated between the covering plate portion and the case, wherein a transparent window portion, which enables visual recognition of the recorded/unrecorded regions of the disc medium, is provided each at a region of the covering plate portion which region is other than a region where the shutter portion is disposed when the opening is closed, and in a portion of at least one of the top shell and the bottom shell which portion corresponds to the region of the covering plate portion at which the transparent window is provided.
With such a structure, the recorded/unrecorded regions of the disc medium can be easily visually confirmed from the exterior. Thus, the approximate unrecorded amount of the disc medium can be easily recognized, and the convenience of use of the disc cartridge can be improved as compared to the prior art. Further, the transparent window is provided at a position which is not covered by the shutter portion at the time when the shutter portion closes the opening. Thus, the approximate unrecorded amount can be suitably recognized at times when the disc cartridge is not in use.
The disc cartridge of the third aspect of the present invention is a disc cartridge having: a case which is formed by joining a top shell and a bottom shell, and which rotatably accommodates a disc-shaped disc medium which can be recorded on at least one time and at which recorded/unrecorded regions can be visually identified; an opening, provided in the case, for access to the disc medium; a shutter portion which is provided at an outer side of the case and at a disc medium recording surface side of the case, and which opens and closes the opening; and a covering plate portion in which an opening for access to the disc medium is formed, the shutter portion being movably accommodated between the covering plate portion and the case, wherein the covering plate portion is formed by a transparent member, and a transparent window portion, which enables visual recognition of the recorded/unrecorded regions of the disc medium, is provided at a region of one of the top shell and the bottom shell which region is other than a region where the shutter portion is disposed when the opening is closed.
With such a structure, the recorded/unrecorded regions of the disc medium can be easily visually confirmed from the exterior. Thus, the approximate unrecorded amount of the disc medium can be easily recognized, and the convenience of use of the disc cartridge can be improved as compared to the prior art. Further, the transparent member is provided at a position which is not covered by the shutter portion at the time when the shutter portion closes the opening, and the covering plate portion is transparent. Thus, the approximate unrecorded amount can be suitably recognized at times when the disc cartridge is not in use.
The disc cartridge of the fourth aspect is a disc cartridge having: a case which is formed by joining a top shell and a bottom shell, and which rotatably accommodates a disc-shaped disc medium which can be recorded on at least one time and at which recorded/unrecorded regions can be visually identified; an opening, provided in the case, for access to the disc medium; a shutter portion which is provided at an outer side of the case and at a disc medium recording surface side of the case, and which opens and closes the opening; and a covering plate portion in which the opening for access to the disc medium is formed, the shutter portion being movably accommodated between the covering plate portion and the case, wherein the covering plate portion is formed by a transparent member, and one of an aperture and a cut-out portion, which enables visual recognition of the recorded/unrecorded regions of the disc medium, is provided at a region of one of the top shell and the bottom shell which region is other than a region where the shutter portion is disposed when the opening is closed.
With such a structure, the recorded/unrecorded regions of the disc medium can be easily visually confirmed from the exterior. Thus, the approximate unrecorded amount of the disc medium can be easily recognized, and the convenience of use of the disc cartridge can be improved as compared to the prior art. Further, by making the covering plate portion transparent, it suffices to provide an aperture or a cut-out portion only at the top shell and/or the bottom shell. Thus, the manufacturing costs can be decreased.
In the disc cartridge of the fifth aspect, in the disc cartridge of any of the second through fourth aspects, the window portion and the aperture and the cut-out portion are formed substantially radially in substantial correspondence with a length from an inner periphery to an outer periphery at a recording surface of the disc medium. With such a structure, the recording region of the disc medium is formed from the inner periphery thereof toward the outer periphery thereof. Thus, the recorded region and the unrecorded region thereof can be reliably recognized.
In the disc cartridge of the sixth aspect, in the disc cartridge of any of the second through fifth aspects, a scale, which enables recognition of a capacity of one of a recorded region and an unrecorded region of the disc medium, is provided at one of the transparent window portion and the transparent member. With this structure, the accurate recorded amount or unrecorded amount of the disc medium can be easily grasped merely by reading the scale. Thus, the convenience of use of the disc cartridge can be improved even more.
In the disc cartridge of the seventh aspect, in the disc cartridge of any of the second through sixth aspects, at least one of the transparent window portion and the transparent member is formed of a material which attenuates transmission of neighboring wavelengths including a recording wavelength of the disc medium. In this way, the deteriorating effects of ultraviolet light on the recording surface of the disc medium can be prevented.
In the disc cartridge of the eighth aspect, in the disc cartridge of any of the second through sixth aspects, a substance, which attenuates transmission of neighboring wavelengths including a recording wavelength of the disc medium, is applied on at least a surface of at least one of the transparent window portion and the transparent member. In this way, the deteriorating effects of ultraviolet light on the recording surface of the disc medium can be prevented.
In the disc cartridge of the ninth aspect, in the disc cartridge of any of the second through sixth aspects, a substance, which attenuates transmission of neighboring wavelengths including a recording wavelength of the disc medium, is kneaded into at least one of the transparent window portion and the transparent member. In this way, the deteriorating effects of ultraviolet light on the recording surface of the disc medium can be prevented.
The disc cartridge of the tenth aspect is a disc cartridge in which an opening, which is for accessing a disc-shaped disc medium, which is provided in a case which rotatably accommodates the disc medium, is, at a time of non-use of the disc medium, closed by end surfaces of a first shutter member and a second shutter member abutting one another, and at a time of use of the disc medium, opened by the first shutter member and the second shutter member moving in respectively different directions, the disc cartridge comprising: a first urging member for urging the first shutter member in a direction of closing the opening; and a second urging member for urging the second shutter member in a direction of closing the opening.
In the disc cartridge of the tenth aspect, the opening for accessing the disc medium is provided in one surface or in both surfaces of the case which rotatably accommodates the disc medium which is disc-shaped. When the disc medium is not in use, end surfaces of the first shutter member and the second shutter member abut one another, such that the opening is closed. Accordingly, entry of dust or the like into the case is prevented.
At the disc cartridge, when the disc medium is in use (e.g., when the disc cartridge is being loaded into a drive device or after loading has been completed), the first shutter member and the second shutter member move in respectively different directions so as to open the opening. Then, the disc medium can be accessed from this opening. Namely, the disc medium is operated from this opening (e.g., is rotated by a rotation spindle shaft, or laser beam is illuminated thereon by a laser head), and recording or playback of information is carried out.
Here, because the first urging member and the second urging member are provided, at the time when the opening is closed from the state in which the opening is open, the first shutter member is moved to the position of closing the opening by the urging force of the first urging member, and the second shutter member is moved to the position of closing the opening by the urging force of the second urging member. Thus, the first shutter member and the second shutter member are appropriately urged in accordance with the respective moving directions thereof, and each can move (operate) smoothly. Further, because the first shutter member and the second shutter member move to positions of closing the opening merely due to the urging forces, the opening can be reliably closed without deformation such as buckling or the like as in the prior art.
Moreover, the first shutter member and the second shutter member are respectively urged independently. Thus, the urging forces by the first urging member and the second urging member do not become too large, and handling of the urging member at, for example, the time of assembly is easy. In this way, in the disc cartridge of the tenth aspect, the pair of shutter members operate smoothly, and the opening, which is for access to the disc medium accommodated in the interior, can be reliably closed.
The disc cartridge of the eleventh aspect is a disc cartridge having: a case having a tubular wall which is formed in a substantially tubular shape, the case rotatably accommodating a disc-shaped disc medium at an inner side of the tubular wall; an opening, provided in the case, for access to the disc medium; a first shutter member which is formed so as to be able to close a portion of the opening, and which has a circular-arc-shaped guide portion which curves along the tubular wall; and a second shutter member which is able to close a remaining portion of the opening, and at a time of non-use of the disc medium, end surfaces of the first shutter member and the second shutter member abut one another and the opening is closed, and at a time of use of the disc medium, the circular-arc-shaped guide portion moves along the tubular wall, the first shutter member rotates, the second shutter member moves in a direction different than the first shutter member, and the opening is opened, wherein the disc cartridge comprises: a first urging member for urging the first shutter member in a direction of closing the opening; and a second urging member for urging the second shutter member in a direction of closing the opening.
In the disc cartridge of the eleventh aspect, the opening for access to the disc-shaped disc medium is provided in the case in which the disc medium is rotatably accommodated at the inner side of the tubular wall. When the disc medium is not in use, end surfaces of the first shutter member, which can close one portion of the opening, and the second shutter member, which can close the remaining portion of the opening, abut one another, so as to close the opening. Thus, entry of dust or the like into the case is prevented.
In this disc cartridge, when the disc medium is in use (e.g., when the disc cartridge is being loaded into a drive device or after loading has been completed), the circular-arc-shaped guide portion moves along the tubular wall and the first shutter member rotates, and the second shutter member moves in a direction different from the first shutter member, such that the opening is opened. Then, the disc medium can be accessed from this opening. Namely, the disc medium is operated from this opening (e.g., is rotated by a rotation spindle shaft, or laser beam is illuminated thereon by a laser head), and recording or playback of information is carried out.
Because the first urging member and the second urging member are provided, when the opening is closed from the state in which the opening is open, due to the urging force of the first urging member, the first shutter member rotates to a position of closing the opening while the circular-arc-shaped guide portion moves along the tubular wall, and due to the urging force of the second urging member, the second shutter member moves to a position of closing the opening. Thus, the first shutter member and the second shutter member are appropriately urged in accordance with the respective moving (rotating) directions thereof, and each can move (operate) smoothly at the time of closing the opening. Further, because the first shutter member and the second shutter member move to positions of closing the opening merely due to the urging forces, there are no regions at which deformation, such as buckling or the like, occurs as in the prior art, and the opening can be reliably closed.
Moreover, the first shutter member and the second shutter member are respectively urged independently. Thus, the urging forces by the first urging member and the second urging member do not become too large, and handling of the urging member at, for example, the time of assembly is easy. In this way, in the disc cartridge of the eleventh aspect, the pair of shutter members operate smoothly, and the opening, which is for accessing the disc medium accommodated in the interior, can be reliably closed. In this way, the first shutter member is guided by the tubular wall at the circular-arc-shaped guide portion, and operates reliably.
Further, in this structure, the moving resistance of the first shutter member, which has the circular-arc-shaped guide portion which moves (slides) along the tubular wall, is large. However, the first shutter member is urged by the first urging member in the direction of closing the opening, independently of the second shutter member. Thus, due to the urging force of the first urging member, the first shutter member can smoothly close the opening. Further, the urging force (e.g., in a case in which a spring is used, the spring constant thereof) of the second urging member, which urges the second shutter member, does not become too large. Handling of the urging member at, for example, the time of assembly is easy, the disc cartridge does not become large-sized, and the opening for access to the disc medium can be made large.
In the disc cartridge of the twelfth aspect, in the disc cartridge of the eleventh aspect, the first urging member is a coil spring whose one end portion is connected to the circular-arc-shaped guide portion, and whose another end portion is connected to the case, and which expands and contracts along the tubular wall. In the disc cartridge of the twelfth aspect, the first shutter member is urged in the direction of closing the opening, by the coil spring which expands and contracts along the tubular wall.
In this way, when the first urging member is a coil spring which expands and contracts along the tubular wall, urging force in the tangential direction or in the peripheral direction of the tubular wall can be applied, with a simple structure, to the first shutter member which is rotated by the circular-arc-shaped guide portion moving along the tubular wall (i.e., it is not necessary to have a rotation shaft). Thus, the structure is even more suitable. Moreover, one end portion of the coil spring is connected to the circular-arc-shaped guide portion which moves along the tubular wall at whose inner side the disc medium is accommodated. Thus, the rotation moment of the first shutter member due to the urging force of the coil spring is large (the spring constant can be made small), which is suitable.
In the disc cartridge of the thirteenth aspect, in the disc cartridge of the eleventh aspect, the first urging member is a power spring whose one end portion is connected to the circular-arc-shaped guide portion, and whose another end portion is connected to the case, and which is pulled-out and wound-up along the tubular wall. In the disc cartridge of the thirteenth aspect, the first shutter member is urged in the direction of closing the opening, by a power spring (which may be a spiral spring) which is pulled-out and taken-up along the tubular wall.
In this way, when the first urging member is a power spring which is pulled-out and taken-up along the tubular wall, urging force in the tangential direction or in the peripheral direction of the tubular wall can be applied, with a simple structure, to the first shutter member which is rotated by the circular-arc-shaped guide portion moving along the tubular wall (i.e., it is not necessary to have a rotation shaft). Thus, the structure is even more suitable. Moreover, one end portion of the power spring is connected to the circular-arc-shaped guide portion which moves along the tubular wall at whose inner side the disc medium is accommodated. Thus, the rotation moment of the first shutter member due to the urging force of the power spring is large (the spring constant can be made small), which is suitable.
The disc cartridge of the fourteenth aspect of the present invention is a disc cartridge having: a case which is formed by joining a top shell and a bottom shell, and which rotatably accommodates a disc-shaped disc medium at an inner portion; an opening which is provided by being cut-out in a substantial U shape, as seen in plan view, from an end portion of the bottom shell, and which is for access to the disc medium; a shutter portion which is provided at an outer side of the bottom shell, and which opens and closes the opening; and a covering plate portion which has an opening which is provided by being cut-out in a substantial U shape, as seen in plan view, from an end portion so as to overlap said opening, the shutter portion being movably accommodated between the covering plate portion and the bottom shell, wherein a connecting member spans along an outer configuration of the bottom shell between end portions of the opening provided in the bottom shell.
With this structure, the strength of the bottom shell can be improved, twisting arising at the opening end portion of the bottom shell can be prevented, and the flatness of the bottom shell can be suitably ensured. Thus, the drawback of the rotatability of the shutter portion deteriorating does not occur. Accordingly, inappropriate contact with the bottom shell can be prevented, and the generation of dust or the like can be prevented. Thus, the occurrence of errors at the time of recording and playback can be reduced.
The disc cartridge of the fifteenth aspect is a disc cartridge having: a case which is formed by joining a top shell and a bottom shell, and which rotatably accommodates a disc-shaped disc medium at an inner portion; an opening which is provided by being cut-out in a substantial U shape, as seen in plan view, from an end portion of the bottom shell, and which is for access to the disc medium; a shutter portion which is provided at an outer side of the bottom shell, and which opens and closes the opening; and a covering plate portion which has an opening which is provided by being cut-out in a substantial U shape, as seen in plan view, from an end portion so as to overlap said opening, the shutter portion being movably accommodated between the covering plate portion and the bottom shell, wherein an end portion of the opening provided in the bottom shell is fixed to an inner surface of the top shell.
With this structure, because the top shell is rigid, by fixing the opening end portion of the bottom shell to the inner surface of the top shell, the strength of the bottom shell can be improved. Accordingly, twisting arising at the opening end portion of the bottom shell can be prevented, and the flatness of the bottom shell can be suitably ensured. Thus, the drawback of the rotatability of the shutter portion deteriorating does not occur. Accordingly, inappropriate contact with the bottom shell can be prevented, and the generation of dust or the like can be prevented. Thus, the occurrence of errors at the time of recording and playback can be reduced.
The disc cartridge of the sixteenth aspect is a disc cartridge having a shutter portion which can open and close an opening for access to a disc-shaped disc medium, which opening is formed in at least one surface of a case which rotatably accommodates the disc medium, wherein a push portion for fingers at a time of loading the disc cartridge into a drive device is provided at a rear surface of the case.
By providing such a push portion, at the time the disc cartridge is loaded into the drive device, due to the user pressing the push portion with his/her fingers, the user can load the disc cartridge while applying force thereto parallel to the direction of loading. Accordingly, loading into the drive device can be carried out smoothly and stably.
In the disc cartridge of the seventeenth aspect, in the disc cartridge of the sixteenth aspect, the push portion is provided at a center of the rear surface or at a center from the rear surface to at least one of a top surface and a bottom surface. In this way, force can reliably be applied parallel to the loading direction.
In the disc cartridge of the eighteenth aspect, in the disc cartridge of either the sixteenth or seventeenth aspect, the push portion is formed in a concave shape. In this way, the user can easily recognize the push portion.
In the disc cartridge of the nineteenth aspect, in the disc cartridge of either the sixteenth or seventeenth aspect, the push portion is formed in a convex shape. In this way, the user can easily recognize the push portion.
In the disc cartridge of the twentieth aspect, in the disc cartridge of any of the sixteenth through nineteenth aspects, the push portion is subjected to a surface roughening treatment. In this way, force can reliably be applied without the fingers slipping off of the push portion, and even more stable loading can be carried out.